Had a friend stop by the other day to look at my 28 Chevy truck and he brought be a "gift". A set of 4 NOS Firestone Polonium spark plugs with pink insulators that fit the truck and the box says "radioactive" and looks like they are from the 30s-40s. I have been around old stuff like this since I was a kid in the 60s, but this was a first! Anybody ever hear of them and should I get rid of them, or is it ok to use them as long as I am wearing a "Hot Suit". Anyone know where I could find a giger counter to check them out? Hate to put them in the truck and find out later I will have to pay to dispose of 3000 lbs of radioactive material!!!

You are safe...

Check it out here:

http://www.orau.org/ptp/collection/consumer%20products/sparkplugs.htm

It's not mentioned in the link above, but polonium-210 degrades to lead and not another radioactive material. Just because something degrades doesn't necessarily mean it isn't a problem, but in this case it does.

Still, I wouldn't carry one around in my pocket.

The Polonium isotope was the active part of the anti-static dust brushes used by photographers etc. for decades for removing lint and dust from lenses, copyboards, and the like. Even then in those heady days before Federally-mandated warning labels, you were warned not to touch the strip. I defer to others on the half-life and degradation of the material but kind of think there is no risk at this point in time.

With the spark plugs installed in the engine there is no risk from the radiation from the polonium. If they are in the cardboard box they came in there is no risk since the alpha particles are stopped by the cardboard or a piece of paper.
The operating principle is similar to a smoke detector that also uses an alpha emitter, americium, to ionize smoke particles in the chamber near the americium alpha particle source. The ionized smoke particles cause a small current flow that the circuitry detects and then sounds the horn. As the previous article states the buildup of carbon or other materials on the electrodes would limit the ionizing capability of the polonium so I doubt there was much improvement.
Joe, BCA 33493

Based on the published half-life, about 0.6% of the radioactive material is left. Probably not detectable relative to back ground radiation. If you are curious, you can bring the plugs to just about any college or university with a biology or physics department to get a reading using a Geiger counter.

Wasn't Polonium the substance used to kill that Russian that spoke out against Putin? .........Steve

Plutonium!

Yup.

http://en.wikipedia.org/wiki/Alexander_Litvinenko_poisoning

It was polonium-210. Probably in a soluble form and likely ingested by the victim. In this case the dose was received directly in the gut and vital organs including blood. Horrible way to die. Less suffering if the usual Soviet method of a bullet in the head was used.
Joe, BCa 33493

All he had to do was drink it, like the link suggests. P-210 can be carried in a vial of water, and transported all over international airports without suspicion.

Remember when radium glow in the dark watches were considered totally safe?

The dial painters got most of the dose. They used to lick the brush bristles to "point" them to make it easier to paint the small numerals.
Joe, BCA 33493